Control-valve mechanism



June 17, 1930. R. M. GALLowAY 1,764,099

CONTROL VALVE MECHANISM A Filed May 27. 1927 5 Sheets-Sheet l Snom/woz i M Q R. M. GALLOWAY CONTROL VALVE vMECHANIS'NI June 17, 1930.`

Fiied May 27, 1927 5 Sheets-Sheet 2 WMM, @ff/tommy June 17, 1930. R. M. GALLowAY I CONTROL VLVE MECHANISM Filed May 27. 1927 3 She'et-Sheeb 3 Nh. QM.

@noauto/c 6N Nm.. En.

h. HWK. .NW M W0 www m M u W W nu @NANNI wa mw SOW Wn. m

A hwnw/ Patented June I7, 1930 MTEDsTATE-s PATENT OFFICE ROBERT M. GALLOWAY, OF RICHMOND, INDIANA, ASSIGNOR T THE NATIONAL AUTO- ,l

MATIC TOOL COMPANY, 0F RICHMOND, INDIANA, CORPORATION OF INDIANA.

CONTROL-VALVE MECHANISM Application lfiled May 27, 1927. .Serial No. 194,746.

This invention relates to valve mechanisms for controlling the action of hydraulic trans- A missions such, for example, as are used to effect reciprocatory movement of an element forming a part of a machine tool.

Many types of machine tools include an element required to be translated in forward and reverse direction and at varying rates. A drilling machine is a good example of a machine tool of this nature, the drill head constituting the element to be translated and the varying rates of travel being utilized 1st: rapidly to move the head forwardly to advance the tools to the work; 2nd: slowly to feed the drills into the work while they are being rotated; and 3rd: rapidly to retract the tools after the drilling operation is completed.

This invention has for an object to provide an improved and simplified valve mechanism for so controlling the operation of the hydraulic transmission that a reciprocable member automatically may be given its various rates and directions of movement in a predetermined sequence.

Another object of the invention is to provide an improved and simplified valve mechanism, for the above noted. purpose, by means of which the rate of slow feed of the translatable member may be very accurately regulated. i'

Still another object is to provide an improvide and simplified valve mechanism for the above noted purpose which is easy and inexpensive to manufacture, which completely excludes all dirt, chips, and other foreign matter, and which more readily maybe actuated than prior devices.

Other objects and advantages will bein part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in thelart so fully to lapprehend the underlying features hereof that they may embody the same-in the various Ways contemplated by this invention, drawings depictinga preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which Fig. lis a longitudinal sectional view of the improved valve mechanism showing it applied to a portion of a machine tool, the parts belng shown in the positions they assume just at the completion of the forward movement of translatable member and just prior to the return movementv of said member. Fig. 2 is a perspective view of an interference member which controls the movement of the valve. Fig. 3 is a Iview similar to Fig. l but showing a modified form of valve mechanism. Fig. 4 is a bottom view of the valve shown in Fig. 3. Fig. 5 is a detail sectional view of the valve, showing, in dottedlines, the valve in position to effect rapid forward traverse of the transl latable member; and in full lines the position to effect slow forward feed, the various ports being shown out of their normal positions and in a single plane better to'illustrate the flow of fluid through the valve. The interference member, in its `various positions, controls the movement of the valve piston and thereby determines the rate and direction of movement of the translatable member. Figs. 6, 7 and 8 are det-ail views showing the interference member of Fig. 3 in three different positions with respect to the valve control rod, which positions effect rapid-forward, slow forward and rapid return-of the translatable member.

The valve controlling mechanism illustrated in Figs. l and 2 is similar to that disclosed in Fig. 22 of my pending application ySerial Number 125,869 filedJuly 30, 1926 of which this application is in part a division.

' `Referring more specifically to the drawings, the invention-is illustrated in connection with a hydraulic transmission adapted to be utilized to reciprocate a member A on a stationary support B. Many types of machine tools comprise relatively reciprocable members and for the purpose of thisdisclosure the member B may be considered the stationary f rame of a drilling machine and A. may be considered the translatable drill head.f It is4 to be understood however that this invention is neither limited. to drilling machines specifically nor to machine tools generally.

To effect relative movement between the members A and B a usual type of hydraulic tion is dependent upon v generally Y large capacity pipe 5, and

' valve Iiecting the conduits 1 and 2 transmission may miss1on may compr other end connected with theV translatable.

memberAas shown at D in Fig. 3. Fluid pres-l sure conduits 1 and 2 connect with the cylinder C at opposite ends of the piston and by alternately admitting fluid into the cylinder through the conduits 1 the member A connected caused to reciprocate.

thereto, will be the rate of iiow of fluid into the cylinder. It will therefore be perceived that if fluid is admitted into the cylinder at a rapid rate the tool head will be given a rapid movement which conveniently may be utilized rapidly to bring the tools from their retracted position to a position wherein they almost engage the work, and also to again retract-the tool head after the tooling operation has been completed. Likewise, when fluid is admitted into the cylinder at a slow rate the tool head is given a slow movement which may be utilized to feed the tools into the Work during the drilling'operation. l

The resent invention provides improved means orautomatically and alternately conwith a suitable source of fluid pressure and for varyin the rate of iow through one of Vsaid con uits. The embodiment of the invention illustrated in Figs. 1 and 2 includes a valve designated as V and comprising a. hollow casing 3 to which is connected a fluid pressure line L, receiving fiuid pressure from any suitable source. yThe conduits 1 and 2 also are connected with thel casing 3 and alternately are brought into communication with the pressureline through the bodily mofement of a valve Kpiston 4. This valve piston isformed with enlarged end portions 4a, slidingly fitted within a bore 3 in the casing 3, and a reduced intermediate portion 4 comprising a fiuid passage. Fig. 1 shows the valve piston in the position in which it has been lshifted to effect rapid return movement of the member A and thereforethe position in which the valve remains when the machine comes to rest. Itwill be 4observed that in this position the pressure line L is connected with the conduit 2. The conduit 1 has two operative connections with the valve casing 3. One of these connections comprisesy a the other consists of a pipe 6 provided with ay flow-restricting 7. Thus it will be understood that when the pressure line is connected with the -pipe 5 a largelvolume of Huid will be admitted into t e cylinder 'C which will effect rapid movement of the mvstlon P and the head connected therewith. en the pipe 6 is connected with the pressure line, to the exand 2 the piston, and

The rate of reciproca--v `other thereby to var clusion of the pipe 5, the rate of ow intoA the cylinder will e greatly reduced due to lthe setting of the s eed regulating valve 7 and the' head A wil be given a slow feeding movement. A drain pipe 8 also is connected with the casing 3 and serves to return to a suitable sump, the fluid exhausted from the cylinder C. With the valve in the position s own in full lines in Fig. 1 the pressure line is connected with the conduit 2 `and therefore Huid under pressure enters the-left end of the cylinder, causin the piston to be moved in the direction in icated b the arrow t. During this Amovement of t e piston the fiuid i-n the right end of the cylinder is exhausted through the conduit 1, pipe'5,

through the bore 3 and pipe 8 to the sump. Likewise whenv the valve is in a. position to connect the pressure line with the conduit 1 (through either pipes 5 or 6) theV reverse movement of the piston is e'ected and the fluid in the left end of the cylinder is exhausted through conduit 2, bore 3 and pipe 8 to the sump. To permit the fluid to flow from the pipe 2 to the pipe 8 the valve piston is formed with a central bore 4.

An important feature of this invention resides in the automatic means for shifting the valve piston from one position to anthe rate and direction of movement o the member A. lAs

shown in Figs. 1 and 2this means comprises.

an interference member 9 slidingly fitted in a suitable bearing bracket 410, which may` be supported by the base B. This interference member is provided with three abutment surfaces 9a, 9b and 9c (see Fig. 2) adapted in certain positions of said member to be in the path of a stop shoulder provided by a collar 11 fixed upon a rod 12 extending through a slot 13 in said interference member and to which the valve piston 4 also is secured, as by a pin p. A coil spring 14, seaty ed within a cavity in the member 9, has one end resting upon a plate 15 attached to the bracket 10 and normall member upwardly to p ace the upper projecting end 9x thereof in the path of dogs 16 and 17 ladjustably mounted on the movable member A. A second coil spring'18, surrounding the rod 12 and interposed between the collar 11 and a bearing bracket 19, in which one end of the rod is slidingly fitted, normally 'acts to force therod 12, andthe valve piston 4 connected therewith, toward acts to move said the left tothe position shown in full lines, in u which the valve effects rapid 'retraction of the member A. This movement is ever, sometimes obstructed by the abutment surfaces 9, and 9b and the rod and the parts connected therewith are permitted to move under the influence of the spring-only as the abutment surfaces are taken out of the path how-- of the collar 11. The do s 16 and 17 actl i upon the member 9 at pre etermined zpoints in the cycle to depress it and thereby intermittently and successively to remove the surfaces 9a and 9b out of the path of the collar thereby permitting the valve piston to be moved to vary the rate and direction of move.-

'ment of the member A, as will now be explained.

Pre-supposing that the machine has cornpleted a cycle and come to rest. The valve piston will be in the position shown in fullv at 21 to a bracket 22,' and moves it toward the right. This lever carries a stud 23 arranged between collars 24 vsecured to the rod 12,

whereby this movement of the lever shifts the rod, the valve piston 4 and the collar 11 from their full line positions to their dotted line positions, in opposition to the spring 18. As the collar 11 is moved out ofthe path of horizontal iats 9d andl 9e on the member 9 this member is moved vertically, by the spring 14, from its full line Iposition to its uppermost dotted position in which the upper end 9* thereof is in the path of movement ofthe dog 16. Extreme upward movement of the interference member (which is limited by the pin and slot connection 25) places the abutment surface 9a in the path 0f the collar 11 which is held thereagainst by the spring 18. In this adjusted position of the valve piston 4 the pressure line L is isolated from the conduit 2 and connected with the conduit 1 through both the restricted ow pipe 6 and the large capacitypipe 5 whereupon fluid under pressure is admitted into the right end of the cylinder at a rapid rate and consequently the piston Pand the member A connected therewith are rapidly moved to the left, it being understood that during movement of the piston to the left the Huid in the left end ofthe cylinder is exhausted through conduit 2, bore 4c and pipe 8 to a sump. This traverse may be utilized rapidly to bring tools 'carried by the member A, substantially into contact with a work-piece. As the head A is traversed toward the left the dog 16 engages the upper end 9c of the interference member 9 and depresses it thereby movingthe abutment surface 9a out of the path of the collar 11 which', together with the rod 12 and valve piston 4, are moved toward the left until the collar 11 abuts the surface 9b of the interference member. This movement of the valve piston causes the enlarged portion 4a thereof to close the port leading to the pipe 5 but maintains the -pipe 6 in connection with the fluid pressure line whereby the flow of fluid into the right end of the cylinders is greatly reduced, correspondingly reducing the rate (but not varying the direction) of travel of the member A.' This slow motion may be utilized to feed tools into a work-piece and the rate 'thereof may be regulated by 'adjustment of A continued movement of the vmember A causes the dog 17 also toengage and depress the interference member thereby movino' the abutment surface 9"V out of the path of the collar whereupon the spring 18 again moves the rod 12, and the collar 11 and valve piston 4 carried thereby to the positions shown in full lines.I It will be understood that in a machine tool this last movement of the valve lwill take place when the machining opera- 'piston the pressure line is disconnected from' the pipes 5 and 6 and is connected with the conduit 2 whereupon fluid, under pressure, flows at a rapid rate into the left end of the cylinder C thereby retracting the member A to its dotted line position where it may be stopped-by any suitable means. During retraction of the member A the fluid in the right end of the cylinder C is exhausted through the conduit 1, pipe 5,' bore 3a and pipe 8 to a suitable sump.

The embodiment of the invention disclosed in Figs. 3 to 8 inclusive operates on the same principle as does that shown in Figs. 1 and 2 but the structural details thereof are somewhat different. In so far as the parts are similar the same reference characters have been usedand in view of the fact that these parts have already been described further description thereof is deemed unnecessary. This modified construction comprises a valve casing 30 (see Figs. 3 and 5) to which are connected a fluid pressure' line L, a, drain 8 and conduits 1 and 2 connected with opposite ends of the cylinder C. Within a cylindrical bore 31 in the casing 30 there is fitted a sleeve l 33, 34 and 35 to an axial bore 39 in said sleeve,

within which bore is slidingly fitted a valve piston 40 later to be referred to. kAn end cap 41 closes one end of the casing 30 and provides a bearing 41a for a valve rod 42 to which the valve piston 40 is connected. The drain pipe 8 is connected withl the cap 41 and communicates with a bore 43 therein which in turn opens into the bore 39 of the sleeve 32. The opposite end of the casing is closed by a sub-casing 44, providing a bearing 45 for the rod 42, and is formed with a bore 46 within which is slidingly fitted an -interf'er ence member 47 later to be referred to.

Referring to Fig. 5, the valve piston 40 is formed with enlarged end portions 40a and 40b slidingly fitted to the bore 39 in the sleeve tioni'40* which constitutes a fluid passage,

' whereby, when the Valvepiston is in its extreme right position as shown in Figs. 3 and 4, it connects the Huid pressure line with the conduit 2 and effects rapid retraction of the.

' member A.1 When the piston 40 is shifted to the position shown in dotted lines in Fig. 5

it connects the pressureline with the conduit 1 and effects rapid forward traverse of the Fig. 5. The means for automatically shifting the piston to its various positions, thereby to vary the rate and direction of movement of the member A, differs in structural details from the means shown in Figs. 1 and 2 for the same purpose, but they both operate on the same general principle. In the modified construction a coil spring 48, surrounding. the rod 42 and interposed between the end cap 41 and a collar 49, secured to said rod, normallytends to move the rod and the valve piston connected thereto toward the right to the positionshown in Fig. 3 in -which it effects rapid retraction of the member -A. This movement, however, is controlled by the interference member 47 in a manner similar to the action of the interference member 9 hereinbefore described. The interference member is slidingly fitted i within the sub-casing 44 and normally is urged upwardly by a spring 5() interposed between said member and an abutmentand guide'block 51 iXed within the bore 46. Within the interference member there is adjustably vmounted, as by screw threads, a

v sleeve 52'in the nature of a hollow screw.

This sleeve may be adjusted axially and maintained in adjusted positions by a lock nut 53. The interference member 47 is formed with an abutment surface 54 against which (in one position of the member) bears Ythe end 42* of the rod 42 thereby maintaining the valve piston inrapid traverse forward position. The end 52* Vof the sleeve also constitutes an abutment for the rod 42 and inasmuch as this end is located back of the surface 54 it effects a different position of the valve piston 40'. The end 52* alsoserves (in another position of the member 47) as an 'abutment for a collar 55 secured to the rod 42, the end 42* of the rod then extending into the hollow sleeve 52. This places the valve 'piston a position to effect rapid return of the member A. v v Dogs 16 and 17 adjustably mounted onthe translatable member A act, during forward movement of said member, successively4 to depress the interference member, whereupon the surface 54, and the'y end 52* of the sleeve 52are moved outy of the path of the end 42*v thereby permitting the. valve iston to be shifted in predetermined steps om theosition shown 'in dotted lines in Fig. 5 to t at shown in Fig. 3. Manual means, comprising a lever 20 fulcrumed-at 21 on a bracket 22 and having astud23 located between spaced collars 24 aiixed to an extension 42 of the rod 42, serves (when the lever is movedl to the. left in Fig. 3) to reset the valve piston to initiate a new cycle.

The cycle of operation is as follows z-The member A having come 'to rest in the position shown in Fig. 3 with the valve piston also in the position shown, the operator grasps the lever 20 and moves it toward the left in opposition to the spring 48. This shifts the rod 42e-42 and withdraws the end 42* from the sleeve 52 and permits the member 47 to be elevated by the spring 50 until the surface 54 is in the path of movement of the end 42*.

(See Fig. 6). This also moves the valve pis-A ton to the dotted line positions shown in Fig.

5 thereby connecting the pressure line L 4with the conduit 1 whereupon Huid under pressure rapidly enters'the left end of the cylinder C and effects rapid forward traverse' of the member A. At a predetermined point, the dog 16 engages the upper end of the interference member thereby depressing it and moving the surface 54 outof the path of the end 42* of the valve rod .42, whereupon lthe spring 48 moves the rod 42 and the valve piston 40 to the right until the end 42* engages the end 52* of the adjustable sleeve 52,

-as shown in Fig 7. This movement of the valve piston causes the enlarged portion 40a of the piston 40 partly to close the ports 37 thereby reducing thel flow ofiiuid through the conduit l and reducing the rate of travel, of the head A. Further translation of the member A at the slow rate brings the dog 17 into engagement with the Iinterference member thereby further depressing it and shifting the end of the sleeve 52 out of the path of the rod end 42". A 's the bore in the sleeve 52 is brought into alignment with the end 42* the latter is moved intothe sleeve until the collar 55 engages the end 52* thereof (see Fig. 8). This places the valve piston in a position where it connects the fluid ressure line with the conduit 2 thereby a mitting fluid into the left end of the cylinder and .effecting rapid retraction of the member A.

It will readily be perceived that the amount of partial closing of the ports 37 may bedetermined by adjustment of the sleeve 52 and that therefore the rate of feed maybe regumapeo lated to a nicety. To give access to the screw sleeve 52 the slotted end thereof is arranged in a chamber 56 in the sub-casing 44 and a plate 57 serves to close said chamber to exclude dirt. The construction and arrangel ment of the distributor sleeve '32 in the casing' Y affords convenient'means for varying the formed with a groove 60 which is entered by the point of a screw 61 sustainedl by the subwhen the dog 17 has vbeen retracted from the member' 47 positively acting means is provided for taking'the 'force of the spring 50.

To that end, a rod 63 is connected with the in- Y terference Vmember 47 andA extends through the spring and block 51. Spaced collars 64 are secured upon the projecting e dof the rod 63. Journaled in bearings 65, p ovided by the Abracket which supports the casing 30, is a rockshat 66 to one end of which is secured an arm 67 which carries a roller 68 arranged between the collars 64. To the other end of the shaft 66 is secured an arm 69 adapted to act upon one end of a slide pin 70 trans'- Y latably mounted in a bearing provided by the -cap 41. The other end of the pin 70 engages a cone 71 xed upon the rod 42, whereby when the rod and cone are shifted to theright .to effect rapid retraction of the member A the elements 71, 70, 69, 66, 67, 68, 64 and 63 co-operate to take the pressure exertedby the spring 50 and thereby maintain the rod 42 strain free and freely movable. As the rod 42 is moved tothe left to reset the valve the -pin 70 rides down the cone and through the elements above described releases the spring and permits it to act upon the interference member to elevate it.

Without further. analysis, the foregoing will so fully reveal the gist of-this invention that others can, by applying current knowledge, readily adapt it for various utilizations by retaining one or more of the features that, from the standpoint of the prior art, fairly constitute essential characteristicsof either the generic or specific aspects'vof this invention and, therefore, such adaptations should be, and are intended to be, y. comprehended within the meaning and range of equivalency of the following claims. Q

Having thus revealed this invention, I claim as new and desire to secure the following combinations and elements, or equivalents thereof, by Letters Patent of United States :f-

1. I n combination, a translatable member; iuid pressuremeans to translate said member; a valve to control the rate and direction shoulder; an interference member provided witha plurality of abutment surfaces adapted successively to engage said stop-sh0ulder to limit the movement of 'said valve; and a plurality of dogs carried by said translatable member and acting successively to depress said interference member to cause said abutment surfaces successively to,` release said stop-shoulder thereby to permit said valve to be moved to its various operative positions. 2. A control device for hydraulic transmissions combining a fiuid pressure line; first and second fluid conduits connected with said transmission; a valve mechanism for alternately connecting said Huid pressure line with said fluid conduits, said valve mechanism comprising a casing provided with al bore with which the pressure line and the conduits communicate, and a valve piston slidable in said bore and provided with, a fluid passage-way, adapted in one position of the valve piston to connect thel pressure line with one of said conduits and in another position to connect the pressure line with the other conduit; manual means to move said valve piston from a position in which it effects communication between the pressure line and. said first conduit to a position in which it effects communication to the second conduit; pressure means acting upon said valve tending to return it to itsl initial position; a single interference member' acting first and second fluid conduits connected' withv said transmission; valve mechanism adapted alternately to connect said Huid pressure line with said fluid conduits, said valve mechanism including a rate and direction control element; .manual means to shift said element in one direction to a position wherein it effects a flow of fluid from said pressure line to one of said conduits at a relatively rapid rate; means vtending to shift .said member in the opposite direction; an

. interference member providing a pluralit of stop surfaces co-operating with a shou der movable with said control element adaptedy successively to prevent the movement of said element; and means to give said member a plurality of movements successively to render said stop surfaces ineffective thereby permitting movement of said control element lfirst to vary the rate of flow through said first conduit and then to eect flow at a rapid rate from said pressure line to said secondI conduit.

4. A control device for hydraulic transmisp sions combining a fluid pressure line; first and second fluid conduits connected with said transmission; valve mechanism including a rate and direction control element adapted alternately to connect said fluid pressurev line with said conduits; means tending to shift said control element in one direction; an interference member having a retaining portion which acts to maintain the element in a position where it eects a maximum flow of fluid from said pressure line to said first conduit; means to shift said interference member temporarily to render it ineffective,

thereby to permit-shifting of said element to a position where it effects a reduced flow of fluid-from the pressure line to the first con duit; a second portion on said interference member adapted temporarily to hold said element in the last named position; and second means .to shift said interference member to render it ineffective to retain said control element in the last named position thereby to permit said element to be moved to a position where it effectscommunication between vsaid fluid pressure line and said secondl conduit. I

5.. Ak control device for hydraulic transmis-v 'slons combining a fluid pressure line; first` and second fluid conduits connected with said transmission; valve mechanism adaptedalternately to connect said fluid, pressure line with 4said conduits, said lvalve -mechanism comprising a casing; a sleeve-arranged within said casingand provided with an intake port permanently connected with said pressure line and two other ports each connected with one of said conduits,- a member slidingly fitted :within said casing and provided with a fluid passage; manual means to shift -v said -member'to a position to effect maximum flowvfrom said intake port to one of the other ports; means tending to shift said member to a position to connect said intake port with thefother of said ports; retaining means to hold said member in its shifted position; and autcunatic 'means actuated by thel hydraulic transmission to render said retaining means l ineffective, thereby 'to permit said member to said-intake port with the other of said ports`.

be moved to a position wherein it connects 6. A control device as set forth in claim l5.,'in which the retaining means com rises a spring-pressed element having ap urality,

piston axially; a .rod connected with said piston; an 'interference member provided .with a first abutment surface adapted tobe engaged by said rod temporarily to prevent movement of said rod and piston in one direction; a second abutment provided by said interference member and `adapted to be engaged by said rod temporarily to maintain said rod and valve piston in another position; means to ladjust the last named abutment axially of said rod to vary the position of said valve piston; means to shift said interference member a plurality of times transverse to the movement of said rod to move said abutments out of the ath of said rod; and a stop stop when the latter has been moved'out of the path of said rod.

8. In combination, a hydraulic transmission including a cylinder, a piston movable therein, first and second conduits connected with opposite ends of said cylinder; a fluid pressure line; a valve mechanism adapted alternately to connect said pressure line with said conduits, said valve mechanism comprising a casingy toI which are connected the fluid Vpressure line and said conduits; a fluid distributing piston slidably mounted within said casing; resilient means tendingA to shift said piston in one direction; manual means to shift said piston in the yopposite direction; an interference member having a first stop adapted to maintain said valve piston inonev osition; automatic means to render said rst stop ineffective; a second stop provided by said interference member adapted to ar- Y rest the movement of said piston and maintain itpin a position\ wherein it reduces the.

low of fluid from said pressure line to said first conduit to reduce the rate ofmovement of said translatable member;.means to vary the position of said stop thereby to vary the ratel of slow movement of said translatable member; and means to render said second stop ineffective thereby to permit said valve piston .to be moved to a position wherein it connects the fluid pressure line with said second conduit.

`shoulder carried y said rod remote from its end and adapted-to engage said adjustable loov 9. .The combination set forth in claim 8 -in Which'the interference member comprises'a spring pressed slide rod and the means for rendering .said member ineffective comprisesdogs, carried by a member, movable with said piston, which act to shift said rod in opposi-l tion tothe spring pressure thereon; 'also in which the first stop comprises an abutment surface on said interference member and in which the second stop consists of a screw" threaded into and adjustable relative to said interference member. 10. A control device for hydraulic transmissions combining a fluid pressure line.; two

fluid -conduits connected with said transmis-i sion; a valve connected with said pressure line and with said conduits and adapted .to control the flow of fluid from the former to vthe latter, said valve comprising a closed said member shifting spring temporarily to v prevent movementof said distributing member; automatic means to render said interference means ineective; and means vto maintain the free end of said rod strain free after said interference member has been rendered 11. 'Fluid control means for luid actuating means for machine toolscomprising valve means operable to a plurality of open posi- Y tions to varythe rate of flow of pressure Huid to vary the rate of movement of said element..

to permit the impositiva means to move said valve to a second one of said open positions :12. A movable member; luid actuating means therefor; and fluid control means for said actuating means to vary the speed of operation of said movable member in a single direction, said fluid control means comprising valve means operable to various open positions to vary the rate of fluid iiow; im-

positive means tending to urge 'said valve in.

one direction; means for moving said valve in the opposite direction against said impositiye means; interference means for restraining -said *valve against said impositive means in "one of said open pos1t1ons;and means for releasing said interference meansii to rmit said valve to move\to a second o; sai open positions,

13. In combination, Va translatable member ;a hydraulic motor connected to translate said member; a fluid pressure line; a valve to control the rate and direction of flow ofliuid from said pressure line to'saidmotor; means -to move said valve from an initial position to a position in which it eifectsa lowof fluid into one end of said motor to move said member in one direction at a predetermined rate means tending to return said valve to its initial position; detent means acting to hold said valve in its adjusted position; means, actuated in timed relation-with the movement of said translatable lmember'torelease said detent means thereby to permit said valve to be movedto 'n intermediate position in end ofsaid motor at a materially diierent rate to vary the rate of movement of said translatable member; second detent means to hold said valve-in its intermediate position; second means actuated in timed relation with Vthe movement of said Amember to release said 'second detentmeans to permit lthe valve to be moved to its initial position to effect retraction of said translatable member.

14. A control for a hydraulic motor combining a viiuid pressure line'; conduits connect-` ed with opposite ends of said motor and adapted to be connected with said pressure line to eii'ect alternately forward and reverse action of said motor; a valve for controlling the flow of fluid from said pressure line to said conduits and to vary the rate of flow into one end of said motor; means to move said valve from an initial position to another position to effect a predetermined iow from said pressure line into one end of said motor; means tending to return. said valve to its initial position; retaining means to hold said valve in its adjusted position; rst means to render said retaining means ineffective therewhich it elects flow of fluid into the said by to permit said valve to be moved to an in- Vof translation of said element; means tending to move said valve through a plurality of positions each of which eects a diierent translation of said element; a member movable with said valve; 'an interference member;

a plurality of abutment surfacesprovided by one of said members; a stop shoulder providedby the other of said members, said stop lshoulder being adapted successively to en- -gage said abutment surfaces to limit the movement of said valve; and a lurality of dogs carried by said translatagle. member and acting successively to depress said interference member to cause said `abutment surfaces and said stop shoulder successively to be released thereby to permit said valve to be moved to its various operative positions. 10 In Witness whereof, I have hereunto sub- 4 scribed my name.

I ROBERT M. GALLOWAY. 

